\\[-1.8ex] Soil Heterogeneity & $-$0.136$^{***}$ & $-$0.052$^{**}$ & $-$0.050$^{**}$ & $-$0.046$^{**}$ & $-$0.050$^{**}$ & $-$0.055$^{**}$ \\ 
  & (0.033) & (0.023) & (0.022) & (0.022) & (0.023) & (0.026) \\ 
\\[-1.8ex] 
Observations & 80,887 & 80,887 & 80,887 & 80,887 & 80,887 & 80,887 \\ 
R$^{2}$ & 0.012 & 0.021 & 0.026 & 0.057 & 0.127 & 0.228 \\ 
